Luteinizing Hormone (LH) strips are a home-based tool for monitoring fertility. They detect a specific hormone in urine, helping to pinpoint the most favorable days for conception and time attempts to conceive. The primary goal is to predict ovulation, the release of an egg.
What a Positive Result Indicates
A positive result on an LH strip signifies a significant increase in Luteinizing Hormone, known as the “LH surge.” This hormone plays a central role in the menstrual cycle by triggering the release of an egg.
When an LH strip shows a positive result, it indicates the LH surge has occurred, and ovulation is imminent. Ovulation typically happens within 24 to 36 hours after the LH surge is detected. A positive result is visually interpreted when the test line on the strip appears as dark as, or darker than, the control line.
When to Attempt Conception
Identifying the LH surge with a positive strip helps define the “fertile window,” which is the period when conception is most likely. This window includes the day of the LH surge and the subsequent 1 to 2 days, encompassing the expected time of ovulation. The egg released during ovulation has a relatively short lifespan, generally viable for fertilization for about 12 to 24 hours.
Sperm can survive within the female reproductive tract for up to five days. Therefore, timing intercourse to coincide with the LH surge and the day of ovulation maximizes conception chances. Engaging in intercourse on the day of the positive LH test and for the following one to two days is recommended to ensure sperm are present when the egg is released.
Getting Accurate Results and Common Scenarios
To obtain accurate results from LH strips, consistent testing practices are important. It is generally advised to test at the same time each day, avoiding the first morning urine unless specifically instructed by the product, as LH levels may not be concentrated enough then. Excessive fluid intake before testing can dilute urine, potentially leading to a false negative result, so limiting fluids for a few hours prior to the test is beneficial. Reading the results within the timeframe specified by the manufacturer is crucial, as readings taken too early or too late may be inaccurate.
Sometimes, a clear positive result may not be obtained, which can be due to several factors. Some individuals may have a very short LH surge, making it easy to miss if testing is not frequent enough. Medical conditions such as Polycystic Ovary Syndrome (PCOS) can cause consistently elevated LH levels, leading to multiple positive results that do not accurately predict ovulation. Certain fertility medications can also influence LH levels, potentially affecting the reliability of the strips. If consistent negative results or confusing patterns occur, consulting a healthcare professional is advisable to understand underlying causes or explore other fertility monitoring methods.